//
//  WBNewFeaureView.swift
//  gc微博
//
//  Created by 高聪 on 16/11/15.
//  Copyright © 2016年 高聪. All rights reserved.
//

import UIKit
// 新特性视图
class WBNewFeaureView: UIView {
    
    @IBOutlet weak var pageControl: UIPageControl!
    @IBOutlet weak var enterButton: UIButton!
    @IBOutlet weak var scrollView: UIScrollView!
    
    // 进入
    @IBAction func enterStatus(_ sender: AnyObject) {
        removeFromSuperview()
    }
    
    class func newFeaureView() -> WBNewFeaureView{
        
        let nib = UINib(nibName: "WBNewFeaureView", bundle: nil)
        let v = nib.instantiate(withOwner: nil, options: nil)[0] as! WBNewFeaureView
        // 从xib 加载的视图是 600X600 的
        v.frame  = UIScreen.main.bounds
        
        return v
        
    }

    override func awakeFromNib() {
        
        // 如果使用自动布局设置的界面，从 xib 加载默认是 600x600 大小
        let count = 4
        let rect = UIScreen.main.bounds
        for i in 0..<count {
            let imageName = "new_feature_\(i + 1)"
            let iv = UIImageView(image: UIImage(named: imageName))
            
            // 设置大小
            iv.frame = rect.offsetBy(dx: CGFloat(i) * rect.width, dy: 0)
            scrollView.addSubview(iv)
        }
        
        // 指定 scrollView 的属性
        scrollView.contentSize = CGSize(width: CGFloat(count + 1) * rect.width, height: rect.height)
        scrollView.bounces = false
        scrollView.isPagingEnabled = true
        scrollView.showsVerticalScrollIndicator = false
        scrollView.showsHorizontalScrollIndicator = false
        
        scrollView.delegate = self
        
        // 隐藏按钮
        enterButton.isHidden = true
    }
    

}

extension WBNewFeaureView:UIScrollViewDelegate{
    
    func scrollViewDidEndDecelerating(_ scrollView: UIScrollView) {
      
        // 1. 滚动到最后一屏,让视图删除
        let page = Int(scrollView.contentOffset.x / scrollView.bounds.width)
        
        // 2. 判断是否最后一页
        if page == scrollView.subviews.count {
            
            removeFromSuperview()
        }
        
        // 3. 如果是倒数第二页，显示按钮
       enterButton.isHidden = ( page != scrollView.subviews.count - 1)
        
        
    }
    
    func scrollViewDidScroll(_ scrollView: UIScrollView) {
        
        // 0. 一旦滚动隐藏按钮
        enterButton.isHidden = true
        // 1. 计算当前的偏移量
        let page = Int(scrollView.contentOffset.x / scrollView.bounds.width + 0.5)
        
        pageControl.currentPage = page
        
        pageControl.isHidden = (page == scrollView.subviews.count)
        
    }
}
